Salman Khan has been called the “messiah of math,” and his free, online Khan Academy has been called the future of education, reaching a mind-blowing 10 million students per month. Of course, it has its share of critics. But one thing it has in abundance is friends in high places. Here are some of Khan’s biggest backers.

The Khan Academy has come a long way since it was incorporated in 2008 by retired hedge fund guy Khan, who started it by recording thousands of educational math videos with himself as the teacher. If you couldn’t tell from the messiah reference, the free online school been insanely hyped, but also drawn skepticism and backlash for undermining credentialed teachers.

But the impact Khan is having is impressive, now offering 6,000 instructional videos and 100,000 practice problems in math, biology, physics, chemistry, economics, and more. Around 350,000 registered teachers also use the videos as classroom aids. The Academy’s staff has also grown, including several computer whizzes, PhD-holders, and now even a few with advanced education degrees. Here are the biggest supporters who got the Khan Academy where it is today:

Bill and Melinda Gates Foundation: Shocking I know, but the biggest education reformer on the block loves Khan Academy. One of its original large supporters, Gates first gave $1.5 million in 2010, but has since poured more than $9 million to the organization, including to carry out Gates’ mission of spreading Common Core standards.

The Broad Foundation: This is one of the philanthropies founded by entrepreneur Eli Broad and wife Edythe, and it's largely devoted to education. Broad made a $4 million grant to help the Academy analyze its most effective online lessons and use that data to help its students and the overall education field.

Google: Another early funder, Google gave $2 million to the group back in 2010. Khan Academy also runs on the Google Cloud platform and is participating in, although not receiving financial support from, the company’s $50 million initiative to encourage girls to code.

O’Sullivan Foundation: The Ireland-based O’Sullivan Foundation in 2011 granted $5 million to Khan, to “accelerate the reinvention of education.” Sean O’Sullivan is the founder of transportation tech company Avego, now called Carma, and a managing director at venture capital firm SOSventures.

The Skoll Foundation: Given that Salman Khan is pretty much your prototypical social entrepreneur, it's no surprise that Jeff Skoll's outfit kicked in $1.25 million in 2012.

J.A. and Kathryn Albertson Foundation: In 2013, this funder supporting education in Idaho gave $1 million to Khan to support a statewide pilot project there, supplementing classroom teaching practices with online videos.

Leona M. and Harry B. Helmsley Charitable Trust: Yes, that Leona Helmsley. The foundation gave $2.2 million last year to develop online tools to help teachers and students meet Common Core standards in math. That includes diagnostic tools to help teachers identify gaps.

The Khan Academy has also landed support from some wealthy individual donors. Netflix founder and streaming video godfather Reed Hastings gave $3 million. Intuit founder Scott Cook gave $1 million. And, of course, Khan Academy has a huge friend in Google's chair Eric Schmidt, who has been a donor and board member and touted the group's innovative approach on 60 Minutes. It also has its share of corporate backers, including Bank of America, Oracle, and tech law firm WSGR.

The list goes on. Khan has grown at an incredible rate in just a few years, no doubt in large part to this team of reform-minded education funders. Now the question is whether its founder's ideas bear fruit and can transform education on the whole, for the better.